C3 Late Model Axle Code

[Tom R.]

The code on my 78 differential reads "OK 311 W 7E 1" My interpretation of the code indicates a 3:08 assembled the 311 day (November) by the Warren Motive Plant. Positraction is by Eaton and the first shift. I realize the W in early years came before the date code but I'm also curious about the "7E" Suggestions?

[Vito C.]

Re: C3 Late Model Axle Code

Tom,

The "7"-is the year 1977 I'm also not sure about the "E" maybe it stands for Eaton Positraction unit. Just a guess about the "E"

[Tom D.]

Re: C3 Late Model Axle Code

E means Eaton Posi., I think.

while the W= Warren, MI Plant

but
W could also mean "Warner Motive Posi." if used in place of the E.

[John H.]

Re: C3 Late Model Axle Code

Eaton Posi units were used in all Corvette diffs from '65-'79, and Dana units were used from '80-'82.

[Tom R.]

Re: C3 Late Model Axle Code

Well the "W" refers to the Warren differential assembly plant while the E refers to the Eaton "postitraction" supplier. The 7 most reasonably seems to refer to the production year for the posi...1977 as Vito suggests.

It seems there were three different axle code sequence configurations used between 1968 through 1982. The first covered 68-69 and perhaps earlier, the second the mid-years (70-77) and the third 78-82.